MailScan stops Spamming and Phishing using a combination
of technologies like Non Intrusive Learning Patterns
(NILP), Greylisting, Real-time Black List (RBL), SURBL,
General Header Tests, MX/A DNS Record Verification,
Reverse DNS, X-SPAM Rules Check and more.

Real-time Black List (RBL)
RBL is a DNS Server that lists IP Addresses of known
Spam sending machines. If the contacting IP is found
to be in one of the blacklisted categories, the connection
is terminated.
SURBL Check
Unlike normal RBLs, SURBL Check works by scanning for
the presence of names or URLs of Spam websites in the
message body.
General Header Tests
MailScan checks the validity of all the headers in the
mail and if any of the headers are found to be invalid,
the mail will be considered as Spam.
MX/A DNS Record Verification
The domain part of the email address in the "MAIL
FROM" SMTP command is checked to see if it has
a DNS MX (Mail Server) and/or A (IP) record as it is
typical of spammers to use non-existent domains in their
emails.
Reverse DNS
A reverse DNS check is performed to see if the connecting
IP resolves to a valid domain name before accepting
or rejecting the email.
X-Spam Rules Check
X-Spam Rules are Rules that describe certain characteristics
of a mail and they are matched against the mail header,
body and attachment to generate a score for each mail.
If the score crosses a threshold value, then the mail
is considered a Spam.
Sender Policy Framework (SPF)
Sender Policy Framework is a world standard that helps
to prevent forgery of sender address and is a powerful
mechanism to stop Phishing mails.
Auto Updates for Spam Detection
The system updates the Bayesian Spam Database with probable
phrases and words.
Power to Block Image Spam
To evade 'word' and 'Phrases' based Spam Control and
Content Scanning software solutions, many spammers today
are increasingly resorting to the use of images in their
mails. The text written inside an image is not scanned
by most security solutions and hence not caught by Spam
blockers. MailScan uses powerful technologies to filter
out image spam.
Autogenerated Spam Whitelist
When a local user sends a mail to an email address,
the system automatically adds that ID to the Spam Whitelist.